In automobile body construction, a body subassembly is constructed using elements which are prepared by being disposed relative to one another in a sort of jig, the jig then being transported to and placed in a station in which the held-together elements are fixed together, in particular by spot welding. A subassembly is thus obtained which, if necessary, is transferred to a second preparation station so that other individual elements can be added. The new, supplemented assembly is then assembled precisely by spot welding.
This operation sequence can be repeated as many times as is necessary to obtain a completed assembly.
Usually, the stations for constructing such an assembly are disposed along a general direction defined by general conveyor means which serve each preparation station, assembly station, and finishing station. An assembly line is thus constituted in which the stations control one another. In such a line, since the stations are numerous and they are disposed in succession, they are ill-suited to making sheet metal assemblies that are different from one another. Furthermore, access to each of the stations of such a line is limited because the space available around each station is limited.